The music in detail: Frontier
Frontier is the only purely electronic piece on the album. I created all of the sounds in this track using the Juno 106, an analogue synthesiser first produced in the 1980s that has been used by musicians as varied as Autechre, The Chemical Brothers and William Orbit.
The creative process was a bit like a musical collage. First of all, I adjusted the parameters of the synth until I found an expressive sound that felt right, then improvised with this sound and recorded short sonic fragments. I repeated this process until I had about twenty contrasting fragments to use as raw material, and I named them according to the image each one conjured up in my mind, such as a "mighty bird", a "fanfare", and a voice asking the question “who are you?". The fragments share a common key note, which unifies them. I then manipulated and arranged these fragments to create feelings of tension and release and a musical structure that "breathed", and this formed the final composition. In doing this, I was guided by the idea of a deserted landscape, which is where the title came from.
When I was creating the raw sounds, I was particularly interested in exploiting to their full potential the sounds and effects on the synth that are not normally used for musical purposes. A simple example of this is the white noise function: usually white noise (hiss) is used to add colour to a pitched, musical sound, but I think there is something beautiful about the opposite sound, i.e. the white noise being in the foreground, with just a hint of a defined note, a bit like whistling wind.
As with most of the album, the harmonic series plays an important role in Frontier (I gave a short explanation of the harmonic series in my post on Fantasia). With some of the sounds, the musical fragment is just a single long note, but the movement comes from the filter function on the Juno 106, which I used to cut out the high overtones of the sound and open them up again in real time. The sound of the filter "opening" and "closing" the high harmonics like this can be accentuated using a function called "resonance", which exists on most synthesisers but is stunningly clear and musical on the Juno 106. In fact, the sound at 01:36 is this resonance function gently whistling the high harmonics.
Although I was manipulating the sonic fragments digitally, and I had access to a whole range of tools to transform the sound, I found I was mostly drawn to simple, more transparent processes. In particular, I used time-stretching: lengthening the fragment, and correspondingly slowing down the speed and lowering the pitch. I was curious as to how far I could stretch the fragment, while still preserving meaningful sounds—albeit sounds where the source was sometimes unrecognisable. This is the technique I used to create the wind sound at the beginning, for instance. An overriding principle I wanted to stick to, to preserve the tonal integrity of the piece, was only stretching the sounds by factors of 2 (2x, 4x, 8x, etc.)—stretching a note "B" by a factor of 2, for example, results in a "B" an octave lower.